Answer: They don't. Women and girls in burkas are susceptible to Vitamin D deficiency.
...Many of these diseases (click here) and manifestations of vitamin D deficiency can be disabling, painful and fatal.
People with high levels of melanin in their skin such as Middle Eastern men and women and people of African descent etc. are at a higher risk of vitamin D deficiency than people of European descent (white people) because the melanin (pigment) levels in their skin are higher, making it more difficult for sunshine to penetrate to the underlying skin layers to make vitamin D.....so they need more sunshine to produce vitamin D in healthy, adequate amounts to sustain healthy body function.
